With a warm roof the usual process is to split the insulation into two layers.
Fitting roof insulation board.
Use a premade kit for this type of project.
Available in both foam and rigid form choose the board type.
If 180mm is to be installed then 100mm board might be introduced between the rafters there has to be a minimum 25mm air gap between the insulation and the underside of the tiles or slates with an 80mm board running across the rafters.
Rigid roof insulation board.
Depending on the specifics of the roof it may be possible to fully fill the rafter depth or in most cases leave a 25mm or 50mm air gap between the top face of the insulation and the.
Hack n stack sealed foam board between the rafters would be better since it s at least an air impermeable insulation but even that would require a vent gap below the roof deck to meet code and you d still be under r38 on that 2x6 rafters unless you fattened it out per holladay s recommendation.
It s light weight provides ease of handling.
Attach the tongue and groove insulation boards to the concrete wall with adhesive.
Follow with a 2x4 frame wall and.
With all the insulation board in place start at the top of the roof and fix the vapour barrier.
Make sure the insulation is 50mm below the actual roof which can be done using the battens as your measuring gauge for the breathable area between the roof and the insulating material.
Here is how we cut and fit our pir insulation to insulate the walls and roof of the house.
Composed of a closed cell polyisocyanurate foam core bonded in the foaming process to 1 2 thick duraboard an expanded perlite mineral aggregate board on one side and a fiber glass reinforced facer on the other.
Before fitting any insulation to the sides of a pitched roof space any repairs to the roof should be completed once the insulation is in place it will be harder to spot any leaks inside the roof and any leaks will soak the insulation itself.
For new construction use rigid boards to insulate slabs and the outside of foundation walls.
For a basement remodeling project consider insulating basement walls with foam board.
Some types of thicker foam board insulation are available but they may need to be special ordered.
Insulation board should be added between the old and new roof systems to ensure proper insulation and to reflect heat from the outside.
This technique is the same for all rigid insulation such as kingsp.
Rigid polyisocyanurate pir foam insulation boards from celotex are among the most thermally efficient commonly available insulation materials on the market.